Estimating alcohol and tobacco consumption of university students and urban population in Ho Chi Minh City by wastewater analysis.

The quantitative measurement of urinary biomarkers in wastewater has emerged as a robust tool for estimating alcohol and tobacco consumption in populations. In this study, we applied the wastewater-based epidemiology (WBE) approach to compare alcohol and tobacco use between university students and urban inhabitants in Ho Chi Minh City, Vietnam. Ethyl sulfate and cotinine serve as markers for alcohol and tobacco use, respectively. Our findings reveal that urban inhabitants aged 15 and above consume 1.56 ± 0.23 mL of pure ethanol and 2.8 ± 0.33 mg of nicotine per day, while university students consume 0.69 ± 0.13 mL of pure alcohol and 1.2 ± 0.2 mg of nicotine per day. This indicates that, on average, students consume less alcohol and tobacco compared with urban adults. A Monte Carlo simulation indicated that, on average, university students in our study smoke 1.5 cigarettes per day, while urban residents aged 15 and above smoke 4.3 cigarettes per day. Considering the smoking prevalence, a student smoker in this study consumes 6.5 cigarettes per day, a level high enough to establish addiction. On the other hand, alcohol use estimation is significantly lower than previous survey-based reports, likely due to degradation within on-site septic tanks. Future research should aim to extend the sampling period to capture seasonal variations and improve the understanding of tobacco and alcohol consumption patterns. The results from this study are crucial for decision-makers in Ho Chi Minh City to develop effective public health strategies and interventions. PRACTITIONER POINTS: Wastewater-based approach is applicable to estimate the tobacco consumption in Ho Chi Minh City. Each current smoker in the urban area of Ho Chi Minh City smokes nearly a package a day. The estimated consumption for student smokers in U-town is 6.5 cigarettes per day, a level high enough to establish addiction. The existence of septic tanks within Vietnam's drainage systems prevents reliable estimation of alcohol consumption for the entire population.

Characteristics of Microplastics and Their Affiliated PAHs in Surface Water in Ho Chi Minh City, Vietnam.

Microplastic pollution has become a worldwide concern. However, studies on the distribution of microplastics (MPs) from inland water to the ocean and their affiliated polycyclic aromatic hydrocarbons (PAHs) are still limited in Vietnam. In this study, we investigated the distribution of MPs and PAHs associated with MPs in canals, Saigon River, and Can Gio Sea. MPs were found at all sites, with the highest average abundance of MPs being 104.17 ± 162.44 pieces/m3 in canals, followed by 2.08 ± 2.22 pieces/m3 in the sea, and 0.60 ± 0.38 pieces/m3 in the river. Fragment, fiber, and granule were three common shapes, and each shape was dominant in one sampling area. White was the most common MP color at all sites. A total of 13 polymers and co-polymers were confirmed, and polyethylene, polypropylene, and ethylene-vinyl acetate were the three dominant polymers. The total concentration of MPs-affiliated PAHs ranged from 232.71 to 6448.66, from 30.94 to 8940.99, and from 432.95 to 3267.88 ng/g in Can Gio sea, canals, and Saigon River, respectively. Petrogenic sources were suggested as a major source of PAHs associated with MPs in Can Gio Sea, whereas those found in Saigon River and canals were from both petrogenic and pyrogenic sources.